He ran so much to lose the weight, he injured his knee and had to spend a couple of months in physical therapy after production wrapped.

Netflix released a trailer of the movie on Tuesday and Franco looks to deliver one of the most dramatic performances of his career.

Dave Franco might be giving his brother James a run for his money as the one in the family who gets deep into character.

In the upcoming Netflix movie “6 Balloons,” Franco plays a heroin addict who over the course of one night is helped by his sister (Abbi Jacobson) to find a detox center while taking care of his 2-year-old daughter.

Netflix release the movie’s trailer on Tuesday (the movie will be available on April 6), and it gives a glimpse of Franco’s most dramatic work yet. And, according to the actor, the role wasn’t easy to pull off.

Franco revealed to Business Insider in November while doing press for his previous movie, “The Disaster Artist,” that he lost 20 pounds for the “6 Balloons” role. The dedication led to some major ramifications both physically and emotionally.

NetflixDave Franco said he ‘almost f—ed up’ his health preparing for his role as a heroin addict in ‘6 Balloons.’

“I was full-on depressed,” he said. “I remember at one point my wife [actress Alison Brie] saying, ‘You’re not yourself, you’re not fun to be around.’ And I was like, ‘I’m f—ing starving! What do you want from me?’ But on set I also wasn’t fun to be around. I wasn’t really interacting with anyone. I was in the corner by myself, miserable.”

Franco said this role is the first time in his career he’s ever gone deep into a character. Looking back, he’s glad he did it, but he also said it “scared the hell out of me.”

“I almost really f—ed up my heath,” he went on to say. “I was running all day every day to lose weight and I ended up messing up my knee to the point that when we finished production I had to go to physical therapy for a couple of months.”

Franco said he got so obsessed with the transformation, he would look at pictures of how Christian Bale has changed his body for roles over the years as motivation.

“If he can do this 15 times I can do it once,” Franco said he would remind himself.

Though it was rewarding to do a role that got Franco out of his comfort zone, when the actor was asked if he would ever do a dramatic transformation like this again for a part he quickly responded: “Not for a long time!”